Plasma processing apparatus

Abstract

A plasma processing apparatus includes a vacuum chamber, a sample table that places the sample in the vacuum chamber, and a gas supply unit faced to the sample table and having a gas supply surface with a diameter larger than that of the sample, wherein gas injection holes each having identical diameter are provided concentrically on the gas supply surface, a hole number density of the gas injection holes present in an outer diameter position of the sample or in an outside of the outer diameter position is made higher than that of the gas injection holes present inside the outer diameter position of the sample, and a diameter of the gas injection holes present in the outer diameter position of the sample or in the outside from the outer diameter position is larger than that of the gas injection holes present inside the diameter of the sample.

Description

BACKGROUND OF THE INVENTION[0001]The present invention relates to a plasma processing apparatus to manufacture semiconductor devices, and in particularly to a dry etching technique to etch semiconductor materials, such as a silicon, a silicon dioxide film, etc., along a mask pattern shape formed by a resist material etc.[0002]The dry etching is a semiconductor micro-fabrication method in which a processing gas is introduced into a vacuum chamber having a vacuum decompression unit, the processing gas is turned into a plasma by an electromagnetic wave to apply it to a sample to be processed, a surface of the sample other than a mask portion is etched to obtain a desirable shape. A processing uniformity on an in-plane sample is affected by a plasma distribution, a temperature distribution on the in-plane of the sample, a supplied gas composition and flow rate distribution, etc.[0003]Particularly, in the case of a parallel plate type plasma processing apparatus, the processing gas is su...

AI Technical Summary

Benefits of technology

[0029]FIG. 6 is a diagram for explaining an advantage of the invention;

[0030]FIG. 7 is a schematic view of a related shower plate;

[0031]FIG. 8 is a diagram showing the relative molecule flux on the wafer surface when a gas-injection-hole number density is made increased at 280 mm (φ280 mm) and its vicinity of the shower plate;

[0032]FIG. 9 is a diagram showing the relative molecule flux on the wafer surface when the gas-injection-hole number density is made increased at 290 mm (φ290 mm) and its vicinity of the shower plate;

[0033]FIG. 10 is a diagram showing the relative molecule flux on the wafer surface when the gas-injection-hole number density is made increased at 300 mm (φ300 mm) and its vicinity of the shower plate;

[0034]FIG. 11 is a diagram showing the relative molecule flux on the wafer surface when the gas-injection-hole number density is made increased at 320 mm (φ320 mm) and its vicinity of the shower plate;

Problems solved by technology

Particularly, in the case of a narrow-gap type apparatus, there sometimes arises a problem to occur a non-uniformity shape at the periphery portion of the sample by causing the non-uniformity of gas supply amount.

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